So what do you think of Class D amp for subwoofers

Thank you Spatialking for agreeing that my quasi classic example of an Aristotelian syllogism contained an intended flaw. In more modern terms, it illustrates a common problem in inductive reasoning.

As for class D 'hysteria', the term being normally associated with excessive and unnatural fears, I have definitely observed such hysteria in these pages. Yet, I suspect you really meant class D zelotry, which instead I still have to notice. having attended this particular audiophilic watering hold for the past 4 or 5 years, I am rather noticing an abating of the aforementioned anti class D hysteria, while the likes of Kijanki, Muralman, and a growing number of others seem to be suggesting that class D amplifiers need be treated individually, like devices of any other class, which inevitably is made of the good, the bad, and the ugly.

The only difference is perhaps that while other types of devices have reached a state of maturity a while ago, and designs seem to be now evolving at a stately rate, some class D designers seem to be on a steep learning curve and are making rapid strides. Case in point is the Bel canto Ref 1000 Mk.2 which I have just reviewed for Positive Feedback. For one thing, it definitely does not yield a stilted bass. See:
http://www.positive-feedback.com/Issue43/bel_canto_ref1000.htm
In case you were asking, no I do not use instruments to perform my admittedly subjective evaluations. . . my ears serve me relatively well and mostly do suffice. G.

Spatialking, Thank you for taking my class D audio journey seriously. My
vocabulary reflects my art training. By using, "Spectrum," I was
likening the highs I am hearing to the color light spectrum derived from
white light run through a prism.

My first modified (by my amp builder, Henry Ho) AN One.1 DAC was a simple
affair. It just wasn't capable of producing a flat frequency measure, and fired
the highs in a bundle, so to speak. I don't mean to say it was terrible
sounding. On the contrary, the little AN trounced a Sony 999 Modright player
so badly, the owner of the Sony bought himself an AMR CD - 77. His system
also includes the H2O amp, this time powering Gallo speakers. I visited the
fellow after his NOS player purchase, and found his speakers sounded
marvelous.

My present DAC is the AN 2.1 DAC, again modified by Henry Ho. Stock AN
DACs tend to be overly pleasant. The diode type used by them is the reason.
Changing them out for some great Shottky diodes opens up the gates for all
frequencies in full strength.

Instead of saving for an even better AN DAC, I am going to wait for Henry to
make his own. Given his track record developing terrific class A amps, and
preamps, not to mention his H2O amps, I can't wait for his DAC.

All of the oversampling players inserted into my system invariably caused the
owners embarrassment. Oversampling players always sound
contrived. The stage flattens, mids are grainy, and the highs are bright.

That's not all! I also found the cable industry is a house of cards. The most
expensive are usually the worst. All hose type cables impart an audible haze
to the music.

The H2O loudly proclaims any defect of any attending component. Why is
this? Class AB and A amps cannot discern the same defects. I know this from
experience with some of the best conventional amps.

I believe it is because the combination of the ultra fast ICE module plus the
ribbon speaker can articulate microscopic detail. This includes any
extraneous radiation bled into the signal anywhere in the chain of
components.

My mantra is, it isn't the better class D amps that are deficient, it is our
understanding of class D that is actually deficient.

Muralman1: An interesting mantra that you have. Consider this along that line of thought: "If our understanding of Class D is deficient, which is in deed a valid argument, then also too are the designers whose understanding is also deficient, which would then yield a deficient amplifier." So, it works both ways.

There is no question in my mind that Class D will get better with time. Better devices and better deign techniques. However, if the bulk of Class D end up in low to mid fi battery operated speakers, then it will be a very long learning curve indeed. As one Class D IC designer told me a while back, efficiency is the sole purpose for Class D's existence, otherwise there is no point. I don't totally agree with that statement, as it is clear that Class D allows for great bang for the buck in higher power amplifiers. I am sure my Marantz amplifier would have cost at least 5x more for the same given output power and the same given number of channels.

I agree entirely that the cable industry is a house of cards. Although I can see the reason for the expense in a number of expensive cables, I do have to question the reasons for the existence of some of the expensive cables indeed. Granted test data does not tell all, but the lack of any test data of any kind is especially suspect to me in the more expensive cables. This is especially true given the great cable test equipment we have today.

Guidocorona: I will check out the review and look for an amplifier here locally. I am curious indeed. I think I might have to pack a small AM radio, too.

Spatialking, The folks at ICE will agree with your summation, in that they will
understandably aim for the market with the most buyers. That is why the
invention of the tiny ASP power supply was such a victory in making the ICE
amps so small. To fit into boom boxes and autos, the amp should be very
small. The problem is, lots of amp manufacturers took this little amp and
stuck it into a pretty box, as you point out.

So then, why did the ICE people even bother making the 500 A module which
requires an add on power supply? The sales for this module must be
miniscule, relegated to only a handful of confident amp builders. Not only did
they go against their mass market appeal strategy, the ICE engineers spent
lots of man hours (expensive) perfecting the 500 A on a second go around.
Was that madness?

I think ICE folks have a sense of pride, and giving great designers like
Rowland and Henry Ho the chance to make great amps out of the 500 A
works to elevate ICE's standing in hi audio.

Henry Ho has succeeded way beyond anyone's dreams in making an amplifier
that is the closest builder have come to create a straight wire with gain. His
amps have no character signature. My super Audio Note DAC, a tubed, non-
oversampling DAC, full access to complete expression through my Apogee
Scintillas.

Of course, as I pointed out above, superior sound is dependent on the rest of
the components in line as well. My experimentation with system components
brought about success upon success.

I can show anyone, on my system, how upsetting just one system link will
devastate the sound. It's a hoot to hook up $10k cables, 20k preamps, or
even $30k CD player. The gorgeous sound will collapse every time.